/**
 * 
 * @param {处理跨域请求，接收app.js 传来的值} app 
 */
exports.CrossDoman = (app) => {
    app.all('*', function (req, res, next) {
        res.header('Access-Control-Allow-Origin', '*');
        res.header('Access-Control-Allow-Headers', 'Content-Type, Content-Length, Authorization, Accept, X-Requested-With , yourHeaderFeild');
        res.header('Access-Control-Allow-Methods', 'PUT, POST, GET, DELETE, OPTIONS');
        if (req.method == 'OPTIONS') {
            res.send(200);
            /让options请求快速返回/
        } else {
            next();
        }
    });
}